Electronic computing device



Filed Aug. 25, 1942 ADLESLI E FL'oRy f BH C.

(Ittorncg UNITED STATES ELECTRONIC COMPUTING DEVICE George A. Morton, Haddon Heights, and Leslie E. Flory, Oaklyn, N. J.. asslgnors to Radio Corporation of America, a corporation of Delaware Application August 25, 1942, Serial No. 456,012

17 Claims. (Cl. 25o-27) 2 l This invention relates generally to electronic application of the applied pulses, whereby the computers and particularly to a cathode ray tube deflection is accomplished in discrete steps. circuit for counting voltage pulses wherein the y Among the objects of the invention are to procathode ray traverses a target electrode of the Vide a new and improved method of and means cathode ray tube in accurately dened discrete 5 fOr Counting vltege PulSeS- Another object is t0 steps. provide a new and improved method of and means Heretofore various devices have been disclosed for Counting V01tage pulses. Which includes a in the of electronic computers cathode ray tube and associated Circuits in which the deection of a cathode my m respcnse to the cathode rayis deflected in discrete steps across voltages or pulses representative of the quantilo an sperm-red shlellelectrode lll response t the ties under computation. Due to the non-linearity applied pulses- Anotllel Obleells t0 Provide a of the defiecung elements of standard cathode new and lmproved method 0f and means for comray tubes, various devices and circuits have been pensatlng for non'llnearty m the deectmg ele' utilized to compensate forerrors introduced by ments 0f a Cathode ray tube, wherein the cathode these factors. For example. compensation for l5 ray is deflected to a predetermined aperture in a non nneaty in the deflection of a cathode my screen electrode, and is maintained within the tube is disclosed in the United States Patent No. boundslles ef seld aperture ulltll s' sueeeedlng 2,415,190 granted to Jan A Rajchman on Febm pulse is applied to the device. Still another object is to Provide an improved method of and means a 4, 1947, wherein the actual deflection of the chode ray provides a predetermined function for returning the cathode ray beam to an initial of the variable quantities applied to the device as pgslolafsl llll llllplste scalllllllg operation variable deecting voltages. e ge e s e The invention will be described in detail by m un .stilstaandestamarmi to of which mg specially designed target electrodes. in com the single figure is a schematic circuit diagram bination with vacuum tube circuits for stepping oflelgeloeglllgo glalhsllgl tube H the cathode lay beam alellgs'plsdesel'mllled paul includes a cathode I2 a. ontrol electrcde I3 a ell .s target electrode lll response so appllell pulses screen electrode I4, and an anode I5 which are Whlsll legeplileselllstve iol the qllialltltles ttlllos supplied with operating voltages from the voltage counts lle. y t e ev se compl ses e' ses e divider I6. A source of high voltage is connected lay tube llsvlllg sellvelltlolls'l cathode' colltlol across the voltage divider I6 A resistor I1 is conelectrode, and anode electrodes. Deilection of the nected between the control electrode I3 and the cathode ray is provided by either electrostatic or electromagnetic deflection elements of conven negative telmllla'l of elle voltage dlvldel le' The I tional design. The cathode ray beam is focussed tube l includes deectmg elements la ls Whlch are located between the anode I5 and an aperllpen a fsl" shleld electrode which includes a tured screen electrode I9. A relatively long tarseries of apertures in the path of the cathode ray get electrode 2u and a relative] y short second beem- Belllnd' and screened by' the mst shleld target electrode 2I are disposed behind the aperelectrode, are two target electrodes. One target 40 tured target electrode |9 The apertures in the TENT OFFICE electrode extends along the greater portion 0f the shield electrode I9 are disposed in the deflection cathode ray path, while the second target elecpath of the cathode my beam The apertured trode is intended for returning the Cihode Tall screen I9 is maintained at a positive potential beam to its initial position upon the completion by means of the battery 22, The long target elecof each full scanning operation. 'I'he associated 45 trode 20 is connected to the input of a D.C. amthermionic tube circuits provide control voltages plmer which incmdes the mst and Second thermifor actuating the deecting elements in response @nic tubes 24 and 25, The output 0f the second to secondary electronic emission from the two thermionic amplifier tube 25 is applied to charge target electrodes. Circuit constants are selected a, capacitor 32, which is connected through a, series to step the electron beam across the apertured resistor 33 to the delecting element I8. The electrode from aperture to aperture in response source of input pulses applied to the terminals to the applied pulses. Nen-linearity of the de- 23 is likewise connected across the series resistor fleeting elements ls compensated for by the asso- 33, whereby the input pulses add or subtract from elated circuits to maintain the cathode ray beam the defiecting voltages normally applied to the within the boundaries of each aperture after the deecting elements IB, I 8'.

The second target electrode 2| is connected to the input circuit of a second amplifier which includes the third and fourth thermionic tubes 28 and 21. The output of the fourth thermionic tube 21 is applied to key the input of a pulse lengthening circuit, for example, a. multivibrator which includes the fifth and sixth tubes 28 and 29. The output of the last multivibrator tube 29 is connected to the movable element of a switch 30, and to the pulse input circuit of the next succeeding counter circuit. One contact of the switch 30 is connected through a capacitor 3| to the control electrode of the cathode ray tube. A second contact of the switch 30 is connected tothe cathode ray deflection electrode lil. A third switch contact is connected to the anode of tube 24. This impulse may also be applied to the next counter tube. or the next counter row in the same tube.

In operation, pulses applied to the input termi- Y nals 23 provide deflection of the cathode ray until it reaches an aperture I in the shield electrode I 9. Electrons penetrating the shield I9 provide secondary electron emission from the long target electrode 20, thereby raising the potential upon the control electrode of the rst thermionic tube 24. This potential is further amplified in the second thermionic tube 25 and applied to the defiecting. elements I8 and I8 to maintain the cathode ray within the connes of the aperture When a second pulse is applied to the input terminals 23 the control potential derived from the target electrode is temporarily overcome, and the ray is deflected until it reaches the second aperture 2 in the screen electrode I9. Penetration of the second aperture 2 by the cathode ray again provides secondary electronic emission from the target electrode 2D, which in turn again locks the cathode ray within the confines of the second aperture 2. Any number and arrangement of apertures may be utilized, depending upon the numerical scale and function thereof desired. Succeeding pulses applied to the input terminals 23 connected across the series resistor 33, increase or decrease the defiecting voltages applied to the deflecting elements I 8, I8 (depending upon the polarity of the applied pulses), and cause the cathode ray to step across the target electrode I9, until the cathode ray reaches the last aperture A. The cathode ray may be stepped in either direction depending on the polarity of the applied pulses. The applied pulses should be of relatively short duration with respect to the time constant of the deflection control circuit including the amplifier tubes 24, 25. The second target electrode 2| is disposed behind the last aperture A. When the cathode ray beam penetrates the aperture A, secondary electronic emission from the second target electrode 2| raises the potential upon the control electrode of the third amplifier tube 26. This potential is further amplified by the fourth amplifier tube 21 and applied to key the multivibrator comprising the tubes 28 and 29. The output of the multivibrator is applied to the switch 3U, which selectively applies the output voltage to the control electrode I3, the deflection element I8 of the cathode ray tube II, or the anode of the amplifier tube 24. When the multivibrator output voltage is thus applied to the control electrode I3 of the cathode ray tube, the cathode ray beam is temporarily interrupted. The interruption of the beam also interrupts the secondary emission from the second collector electrode 2| and the long target electrode 20, whereby the control voltages derived therefrom are also temporarily interrupted. When the con- 4 trol potential is removed from the control electrode of the first amplifier tube 24, the cathode ray beam will be deflected to its initial position on the screen electrode I9, due to the absence of holding potentials.

The control potential derived from the last multivibrator tube 29 may,.if desired, be applied directly to the anode of tube 24 whereby the multivibrator control potential overcomes the normal control potentials derived from the target electrodes 20 and 2| and returns the cathode ray beam to its initial position. It should be understood that in either case the time constant of the multivibrator output circuit should be suicient to permit the return of the cathode ray beam to its initial position. This time constant may be determined by selecting the circuit components in a manner well known in the art. If the amplification provided by the tube 25 is not desired, the multivibrator impulse may be applied directly to the cathode ray tube deilecting element I8.

Thus the invention described comprises a cathode ray tube having an apertured shield electrode and a plurality of target electrodes, with circuits connected to the target electrodes for deriving potentials for controllinfJr the deection of the cathode ray in discrete steps within predetermined regions of the target electrode.

We claim as our invention:

1. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray deecting means, at least one target electrode having a secondary electron emissive surface, and an apertured electrode positioned between said deflecting means and said target electrodes for screening said target electrodes, means for applying said pulses to said ray deiiecting means to deflect said beam across said .L0 target electrodes, and means responsive to said secondary emission for accurately positioning said beam on said target electrode after each application of said pulses to said deflecting means.

2. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray deiiecting means, at least one target electrode, and an apertured electrode positioned between said deiiecting means and said target electrodes vfor screening said target electrodes, means for applying said pulses to said ray deecting means to deflect said beam across said target electrodes and means including said target electrode for accurately positioning said beam in one of said apertures in said apertured electrode after each application of said pulses to said deflecting means.

3. Apparatus of the type described in claim 1 including means for stepping said beam across said target electrode in response to said application of said pulses to said deiiecting means.

4. Apparatus of the type described in claim 2 including means for stepping said beam across said target electrode in response to said application of said pulses to said deflecting means.

5. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray defiecting means, a rst target electrode, a second target electrode, and an apertured electrode positioned between said deflecting means and said rst and second target electrodes for screening said target electrodes, means for applying said pulses to said ray deflecting means to deflect said beam across said target electrodes, and means including said target electrodes for accurately positioning said beam in one of said apertures in said apertured electrode after each application of said pulses to said deecting means.

6. Apparatus of the type described in claim including means for stepping said beam across said target electrodes in response to said application of said pulses to said deecting means.

7. Apparatus of the type described in claim 5 including means including said second target electrode for positioning said ray on a predetermined region of said rst target electrode after application of said ray to said second target electrode.

8. Apparatus of the ty-pe described in claim 5 including a pulse lengthening circuit, means in- -cluding said second target electrode and said circuit for positioning said ray on a predetermined region of said rst target electrode after application of said ray to said second target electrode.

9. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray deilecting means, a rst target electrode, a second target electrode, and an apertured electrode positioned between said deflecting means and said irst and second target electrodes for screening said target electrodes, means for applying said pulses to said ray deflectin-g means to deect said beam across said target electrodes, an ampliiler, means for applying voltages derived from said nrst target electrode to said amplifier, and means for applying said amplied voltages to said deflecting means for accurately positioning said beam in one of said apertures in said apertured electrodeafter each application of said pulses to said defiecting" means.

10. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray deflecting means. a first target electrode, a second target electrode, and an apertured electrode positioned between said deilecting means and said first and second target electrodes for screening said target electrodes, means for applying said pulses to said ray deiiecting means to deiiect said beam across said target electrodes, an amplifier, means for applying voltages derived from said rst target electrode to said ampliiier, means for applying said amplified voltages to said deflecting means for accurately positioning said beam in one of said apertures in said apertured electrode after each application of said pulses to said deflecting means, a second amplifier, a multivibrator, means for applying voltages derived from said second target electrode to said second amplier, means for keying said multivibrator by said second ampliiled voltages, and means including said multivibrator for positioning said ray on a predetermined region of said first target electrode after application of said ray to said second target electrode.

11. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray deflecting means, a first target electrode, a second target electrode, and an apertured electrode positioned between said deilecting means and said first and second target electrodes for screening said target electrodes, means for applying said pulses to said ray deilecting means to deflect said beam across said target electrodes, an amplifier. means for applying voltages derived from said first target electrode to said amplifier, means for applying said amplified voltages to said deecting means for accurately positioning said beam in one of said apertures in said apertured electrode after each application of said pulses .to said deilecting means, a second amplifier, a. multivibrator, means for applying voltages derived from said second target electrode to said second ampliier, means for keying said multivibrator by said second amplied voltages, and means including said multivibrator for positioning said ray on a predetermined region of said target electrode and for temporarily blanking said ray after application of said ray to said second target electrode.

12. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray deecting means, a iirst target electrode, a second target electrode, and an apertured electrode positioned between said deflecting means and said iirst and second target electrodes for screening said target electrodes, means for applying said pulses to said ray deecting means to deflect said beam across said target electrodes, an ampliiler, means for applying voltages derived from said rst target electrode to said amplifier, means for applying said ampliiled voltages to said deecting means for accurately positioning said beam in one of said apertures in said apertured electrode after each application of said pulses to said deflecting means, a second amplier, a multivibrator, means for applying vol-tages derived from said second target electrode to said second amplier, means for keying said multivibrator by said second amplified voltages, and means including said multivibrator and said deflecting means for positioning said ray on a predetermined region of said target electrode after application of said ray to said second target electrode.

13. A cathode ray tube circuit for counting voltage pulses including a cathode ray tube having ray generating means, ray deilecting means, a control grid electrode, a rst target electrode, a second target electrode, and an apertured electrode positioned between said deilecting means and said ilrst and second utarget electrodes for screening said target electrodes, means for applying said pulses to said ray deilecting means to deect said beam across said target electrodes, an amplier, means for applying voltages derived from said rst target electrode to said ampliiier, means for applying said amplified voltages to said deflecting means for accurately positioning said beam in one of said apertures in said apertured electrode after each application of said pulses to said deecting means, a second amplifier, a multivibrator, means for applying voltages derived from said second target electrode to said secondl amplier, means for keying said multivibrator by said second amplified voltages, and means including said multivibrator and said control grid electrode for positioning said ray on a predetermined region of said target electrode after application of said ray to said second target electrode. L

14. In a cathode ray tube having ray generating means, ray deflecting means, an apertured screen electrode, and a target electrode, the method of deilecting said ray in discrete steps across said target electrode comprising directing said ray on said screen, deilecting said ray along a path corresponding to the positions of said apertures in said screen, producing secondary electronic emission from said target electrode in response to penetration of said apertures by said ray, deriving a control potential proportional to said emission, and applying said control potential to maintain said ray within progressive apertures along the path of said ray.

1B. The method according to claim 14 including the step. of deriving a second control potential when said ray penetrates predetermined apertures in said screen, and applying said second control potential to eilectively neutralize said ilrst control potential;

16. The methodaccording to claim 14 including the step of deriving a, second control potential when said ray penetrates predetermined apertures in said screen, and applying said second control potential to eiectively neutralize said iirst control potential and to bias o1! said beam generating means.

17. The method according to claim 14 including the step of deriving a second control potential when said ray penetrates predetermined apertures in said screen, and applying said second control potential to eiectively neutralize said 8 ilrst control potential and to bias od said beam generating means for a predetermined time interval.

GEORGE A. MORTON. LESLIE E. FLORY.

REFERENCES CITED The following references are of record in the o tile of this patent:.

UNITED STATES PATENTS 

